It's just the way that we are.
Chapter one: the reason why.
AN: I don't own the supernatural series or any of the characters, just this story.
It's quiet in the Impala as the two men wind down the stretch of road before them. "Dean where are we going?" says Sam, in annoyance as the silence continues while Dean is thinking about the road ahead and what his dad told about Sam and himself.
Flashback
"Dean you and your brother are soul mates, but Sam ... John trails off, before trying again. "Dean, Sammy will go into heat in the next two days, because the demon blood in his system, he may try to mate with u, Dean I want you to let him mate with you but you must take control, otherwise Sam might never come out the same at the end" explains John, before leaving Dean completely alone...
End of flashback.
"...an, Dean are you even listening to a word I'm saying?" asks a slightly annoyed Sam.
End of chapter one
AN: I know its short but bear with me and you'll get what you want.